To achieve optimal health outcomes for persons living with HIV, several steps along the HIV treatment continuum -- diagnosis, linkage to care, retention in care, use of antiretroviral therapy (ART), and viral suppression -- must be fulfilled. This project, Cooperative Agreement Re-Engagement Controlled Trial (CoRECT) seeks to demonstrate a cost-effective model for improving retention in HIV medical care through Health Department-lead outreach efforts for persons who have fallen out of care. This model could be adopted by Health Departments throughout the United States as a public health program to improve HIV care and reduce HIV transmission. The Philadelphia Department of Public Health (PDPH) will demonstrate over a 5-year period the feasibility of an active care re-engagement intervention jointly implemented by PDPH and six collaborating HIV clinics in the City of Philadelphia which include Ryan White-funded, private, FQHC (Federally Qualified Health Center), and Veterans Administration settings. Patients identified as recently out of care through combined clinic and HIV surveillance data will be randomized to either an active re-engagement intervention from the Health Department or standard of care clinic follow-up. An estimated 600 out of care patients will be identified (300 per arm) from among nearly 5,000 total HIV patients of the collaborating clinics. The primary outcome for CoRECT will evaluate whether patients in the active intervention arm are more likely to achieve viral load suppression within 12 months of the study intervention compared with those receiving usual services. The study's methods are innovative in its planned use of surveillance data, patient-level clinical data, and locating databases to develop rosters of out of care HIV-positive patients. In the active re- engagement arm, Health Department staff will locate clients lost to care and provide intensive re-engagement services. Standard of care clinic-level linkage and engagement services will be provided to all patients and include reminder calls to patients prior to their scheduled appointments, active follow up after missed appointments (i.e. phone calls, letters, etc.). Participating clinics must accept same-day or walk-in appointments referred from the Health Department through the intervention arm. Philadelphia will be one of three project areas conducting the CoRECT study. Philadelphia is the sixth most populous city in the US with an estimated HIV infection rate of 1.3%. Of the 19,832 persons diagnosed with HIV living in Philadelphia, an estimated 54% are not receiving regular HIV medical care. PDPH has developed a comprehensive HIV program to address the epidemic and high quality HIV surveillance, clinical care and partner services are highly coordinated both within the Health Department and in a continuum of contracted provider agencies. PDPH has successfully implemented similar projects and will implement CoRECT based on this experience. Findings from the project will be used in local HIV planning, submitted for publication in peer-reviewed journals as well as professional meetings.